Return Triumphant

Return target creature card with mana value 3 or less from your graveyard to the battlefield. Create a Young Hero Role token attached to it. (Enchanted creature has "Whenever this creature attacks, if its toughness is 3 or less, put a +1/+1 counter on it." If you put another Role on the creature later, put this one into the graveyard.)

Restless Bivouac

Restless Bivouac enters tapped.
{T}: Add {R} or {W}.
{1}{R}{W}: Restless Bivouac becomes a 2/2 red and white Ox creature until end of turn. It's still a land.
Whenever Restless Bivouac attacks, put a +1/+1 counter on target creature you control.

Helping Hand

Return target creature card with mana value 3 or less from your graveyard to the battlefield tapped.

Mountain

Thrill of Possibility

As an additional cost to cast this spell, discard a card.
Draw two cards.

Battlefield Forge

{T}: Add {C}.
{T}: Add {R} or {W}. Battlefield Forge deals 1 damage to you.

Plains

Get Lost

Destroy target creature, enchantment, or planeswalker. Its controller creates two Map tokens. (They're artifacts with "{1}, {T}, Sacrifice this artifact: Target creature you control explores. Activate only as a sorcery.")

Conduit Pylons

When Conduit Pylons enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Guardian of the Great Door

As an additional cost to cast this spell, tap four untapped artifacts, creatures, and/or lands you control.
Flying

Call a Surprise Witness

Return target creature card with mana value 3 or less from your graveyard to the battlefield. Put a flying counter on it. It's a Spirit in addition to its other types.

Inspiring Vantage

Inspiring Vantage enters tapped unless you control two or fewer other lands.
{T}: Add {R} or {W}.

Demand Answers

As an additional cost to cast this spell, sacrifice an artifact or discard a card.
Draw two cards.

Highway Robbery

You may discard a card or sacrifice a land. If you do, draw two cards.
Plot {1}{R} (You may pay {1}{R} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)